The Long-Lasting Aftershock Series of the 3 May 1887 M w 7.5 Sonora Earthquake in the Mexican Basin
The Long-Lasting Aftershock Series of the 3 May 1887 M w 7.5 Sonora Earthquake in the Mexican Basin
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1887 年 5 月 3 日墨西哥盆地里氏 7.5 级索诺拉地震的长期余震系列
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
F. Vernon
中科院分区：
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作者：
R. Castro;P. Shearer;L. Astiz;M. Suter;C. Jacques;F. Vernon
我们研究了来自几个地震台网的局部和区域体波到达时间，以更好地定义1887年5月3日墨西哥索诺拉（南部盆地和山脉省）7.5 Mw地震震中区域的活动断层模式。我们根据当地网络RESNES （Red Sísmica del Noreste de Sonora）和自主记录地震仪网络(NARS) -Baja阵列的台站记录的到达时间确定2003年至2007年间发生的地震的震源坐标。对于2007年4月至12月之间的事件，我们还纳入了位于美国-墨西哥边境150公里内的USArray站点的到达时间。我们首先使用Hypoinverse程序（Klein, 2002）获得初步地震位置，然后使用特定震源站项（SSST）方法重新定位这些初始震源坐标（Lin和Shearer， 2005）。大多数重新定位的震中集中在地壳上层，靠近1887年地震中破裂的断层，可以解释为其持续时间较长的一系列余震的一部分。余震活动区域沿着同一断裂带延伸，位于1887年记录的断裂南端以南40-50公里处，包括1913年5月17日（Imax VIII,MI 5.0-0.4）和1923年12月18日（Imax IX, MI 5.7-0.4） Granados-Huásabas， Sonora地震的震中区域的断层，这些地震本身可能是1887年事件的余震。余震持续时间长可以用主震震级异常大、1887年破裂的断层滑动率低和主震复发时间长来解释。
We study local and regional body-wave arrival times from several seismic networks to better define the active regional fault pattern in the epicentral region of the 3 May 1887 Mw 7.5 Sonora, Mexico (southern Basin and Range Province) earthquake. We determine hypocenter coordinates of earthquakes that originated between 2003 and 2007 from arrival times recorded by the local network RESNES (Red Sísmica del Noreste de Sonora) and stations of the Network of Autonomously Recording Seismographs (NARS)–Baja array. For events between April and December 2007, we also incorporated arrival times from USArray stations located within 150 km of the United States–Mexico border. We first obtained preliminary earthquake locations with the Hypoinverse program (Klein, 2002) and then relocated these initial hypocenter coordinates with the source-specific station term (SSST) method (Lin and Shearer, 2005). Most relocated epicenters cluster in the upper crust near the faults that ruptured during the 1887 earthquake and can be interpreted to be part of its longlasting series of aftershocks. The region of aftershock activity extends, along the same fault zone, 40–50 km south of the documented southern tip of the 1887 rupture and includes faults in the epicentral region of the 17 May 1913 (Imax VIII,MI 5.0–0.4) and 18 December 1923 (Imax IX, MI 5.7–0.4) Granados–Huásabas, Sonora, earthquakes, which themselves are likely to be aftershocks of the 1887 event. The long aftershock duration can be explained by the unusually large magnitude of the mainshock and by the low slip rates and long mainshock recurrence times of the faults that ruptured in 1887.